1. Field of the Invention
The present invention relates to a snowmobile.
2. Description of the Related Art
Conventionally, a snowmobile including an engine, a vehicle body frame formed of a metal material, skis located on a front portion of the vehicle body frame and a track belt driven by the engine is known. A more lightweight snowmobile receives a smaller running resistance while running on the snow. Therefore, the snowmobile is desired to be reduced in the weight. US2013/0032418 A1 discloses a snowmobile including a metal vehicle body frame partially made of a carbon fiber material, which is more lightweight. US2011/0192667 A1 discloses a snowmobile including a bumper made of a carbon fiber material.
Recently, a carbon fiber-reinforced plastic material, which is more lightweight and more rigid than the carbon fiber material, is adopted for a portion of a vehicle body frame. However, it has not been attempted to replace the carbon fiber material with a carbon fiber-reinforced plastic material in a larger portion of the vehicle body frame, and problems and the like caused by the replacement are not known.
In a snowmobile including a vehicle body frame formed of a metal material, an engine is covered with an engine room formed of a metal material, a vehicle body cover formed of a resin material or the like. Such a structure prevents the engine from being exposed to snow. The vehicle body cover or the like is not provided as a reinforcing member for the vehicle body frame but is provided merely to protect the engine against the snow. A vehicle body frame partially made of a carbon fiber-reinforced plastic material and a vehicle body frame partially formed of a metal material have different advantages and disadvantages. Therefore, a structure of the vehicle body frame formed of a metal material by molding cannot be adopted as it is as the structure of a vehicle body frame made of a carbon fiber-reinforced plastic material by molding.